Centrifugal separator.



B. W. KOPKE. CENTRI-FUGAL SEPARATOR.

APPLICATION FILED SEPT. 28, 1911.

1,1 19,175, Patented Dec.1,1914.

WITNESSES: INVENTOR ATTORNEYS UNITED STATES PATENT OFFICE.

ERNST WILHELM KOPKE, OI HONOLULU, TERRITORY OF HAWAII, ASSIGNOR TO KOPKECLARIFIER COMPANY, LIMITED,

A CORPORATION OF THE TERRITORY OF HAWAII.

CENTRIFUGAL SEPARATOR.

Specification of Letters Patent.

Patented Dec.,1, 1914.

To all whom it may concern:

Be it known that I, ERNST W. KOPKE, a citizen of the United States,residing at 1535. Ke'walo street, Honolulu, Territory of Hawaii, haveinvented certai new and useful Improvements in Centrifugal Separators;and I do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

My invention relates to centrifugal machines for clarifyingsugarsolutions and may be employed for separating aggregate liquids orliquids and suspended solids in many branches of industry.

The invention is applicable to a centrifugal separator through which thesolution to be separated is uninterruptedly passed until muds removedfrom the solution by stratification during its passage through themachine collect in the rotating imperforate container in suflicientquantity to render their discharge desirable.

Among other objects the invention is intended to provide a constructionin which the fluid to be Stratified and separated may flow quietlywithout currents, eddies or other disturbances through .the rotatingstratifying chamber, to provide a structure which will admit of thecontinual introduction and discharge of the fluid to andfrom therotating machine and to and from the stratifying chamber, during theperiod in which the mud stratum is formed without permitting theagitation of the fluid which is incident to its introduction, dischar eand angular acceleration to effect distur ances of the fluid in thestratifying chamber.

important when the specific gravities' of the substances to be separatedare but slightly different as in the case of sugar-containing juices andsolutions.

tion of parts hereinafter described and particularlypointed out theappended claims. I have illustrated a centrifugal separator embodyingthe several features of this invention in the accompanying drawing, inwhich- Figure 1 is an elevation,

(partly in section; and is a detaile section of a The attainment ofthese objects is the more The invention onsistsin the peculiarlyadvantageous arrangement and organlzamachine, thus laying rods a dependfrom a supporting head A which is designed to admit of a certain amountof oscillation as is usual in suspended centrifugal machines, and theserods a support a non-rotatlng casing B. The lower part of the casing Bconsists of a casting in the outer edge of which an annular gutter C isformed. Arms D project inwardly from the gutter C and support a ballstep bearing 0 in which the lower end of a rotating shaft E isjournaled. The upper end of the shaft E is journaled in a suitablebearing in the head A, and the usual pulley is mounted fast on the shaftE near this bearing. A spider F has along hub f which is rigidly securedto the shaft E, the arms of which spider carry a rotatable imperforatedrum or annular chamber G. The drum G is cylindrical, its interior beingsmooth and unobstructed, and is provided with an inturned flange g atits upper edge while a peripheral annular rin H upon the spider Fprovides an inturned fiangeupon its lower edge. These inturned flanges gand H form the end walls of an annular stratifying chamber I which isadapted to contain a cylindrical body of liquid when the drum Gis'revolving. A flange j, substantially L-shaped in cross-section, issecured to the bottom of the drum G and forms an annular ante-chamber Jopposite .to the outermost part of which a circular series of apertures72. are provided in the bottom Wall of the drum G, affordingcommunication between the ante-chamber J- and the stratifying chamber I.The sup ply pipe is supported on the casing B passes upwardlybetween thearms D and termimates in a flat nozzle K which lies with its mouthparallel with and at an acute angle to the normal liquid level(indicated by dotted line; a?) in ante-chamber J while the mar hine isin operation, and this nozzle K dish'arges in the direction of rotationof the a flat ribbon of fluid upon the surface ofthe liquid inante-chamber J. The juice flows with all its content of the heaviersolid impurities from the ante-chamber J through the apertures it intothe stratifying chamber I, as an inclination given the outer wall of theflange j deflects any mud which tends to collect thereon toward theapertures h liquid A baflle ring L is mounted a short distance above theapertures h and causes the streams of liquid flowing into the chamber Ithrough the apertures h to impinge upon its underside and spread andflow outwardly over its outer edge, and there join to form a thincylindrical sheet of liquid flowing u 'wardly through the stratifyingchamber The bafile ring L extends within the liquid level and thecountersunk bolts which support it are placed at points without theliquid in order that they will not cause any disturbance within the bodyof liquid. The outer edgeof the baffle ring L should be accuratelyconcentric with the axis of rotation and should be so spaced from thewall of the drum that the rising cylindrical film of liquid enters themain body of the liquid in the stratifying chamber I and in passingtherethrough undergoes a separation of its constituents of differentdensities, the heavier moving outwardly"'and the lighter inwardly,without interference.

At the upper edge of the rotating drum G the inturned flange g ispreferably provided with a channel M the lower wall m of which projectsinwardly farther than the flange g and holds back any lighter impuritieswhich may find their way into the stratifying chamber I, The outer wallof the channel M is proi ided with a circular series of apertures intowhich are slipped tubules N through which the clarified juice rises intothe channel M from that depth in the body of liquid in chamber I fromwhich it is desired to be drawn, and those tubules used of variouslengths and quickly interchangeable serve as convenient means foraltering the depth from which the clarified juice is to be drawn. Itwill thus be seen. that the flange g and channel M with the lower wall mconstitute a dam at the discharge end of the stratifying chamber throughor over which the clarified liquid is discharged from all parts of thatcylindrical'region determined by the selected tubules N. The channel Moffers a convenient place from which the juice may be scooped in thewell known manner if desired but usually it is allowed to overflow theedge of the flange g to be caught by the casing B and drained from thegutter C through outlet pipe 0. A modification of the construction ofthe upper edge of the rotating drum -is shown in Fig. 2, wherein a dam Psimilar to ring L is used, and the clarified is allowed to overflowthrough apertures p in the flange g. The discharge of the clarifiedjuice at the upper edge of the rotating drum must be so controlledhowever, that no disturbances are created within the stratifying chamberI A plow Q is mounted upon the lower end of a racked rod g which ismounted in a bracket R on the casing B and this plow Q is adapted to bemoved downwardly into I and throughout the length of the drum G by theengagement of a pinion with the rack upon rod 9, the pinion beingactuated by a hand wheel 1' on the end of a lever S. The lever S issplined to the rod q and by its angular movement the rod 'g may beturned to bring the plow into engagement with the inner surface of thedrum G in which position it operates to ,remove the layer of mud and maybe moved throughout the length of the drum by hand wheel r.

This machine is designed to carry into I practice the method ofclarification or separation which forms the subject matter of a separateapplication for United States Letters Patent, filed by me of even dateherewith, and identified as Serial No. 651,692.

The operation of the machine is as follows: A fter the machine has beenbrought to speed, the juice is, in ordinary cases, admitted through thenozzle K and in passing through the ante-chamber attains the angularvelocity ofthe machine. The juice gradually accumulates in theseparating chamber until it reaches the normal liquid level indicatedby' the dotted line a; and theoverflow of the clarified juice begins. Incertain exceptional cases it has been found that the first outflow ofjuice from the machine is slightly turbid and in that event,

it is well to interrupt the inflow through the nozzle K for a fewminutes and then reestablish it, when the turbidity will disappear andthe separation may continue. The fluid flowing in through the nozzle Kis laid upon the surface of the liquid already con tained in theante-chamber J, and does not immediately come into contact with any partof the rotating machine but, as it is moved outwardly by the succeedinglayers of in troduced juice, its angular velocity is gradually increasedby friction with the preceding, faster-moving layer, until it comesopposite the apertures h when it will come in contact with the outerwall of the flange j, and will have attained an angular ve locitysubstantially equal to that of the portion of the stratifying chamberinto which it is about to be introduced. The liquid is then traveling atsubstantially the same speed as the apertures h and can flow throughthese apertures quietly into the stratifying chamber I. If the .liquid-has not quite attained the angular velocity of the stratum into which'it is about to be introduced, the walls of the apertures h will give itthe necessary additional speed and it will enter the stratifying chamberI without causing any of the currents or disturbances which would bepresent if it were not stratifying chamber I in a. number of separatestreams from the apertures I; would Ill cause striations in the bodywithin the chamber I which would be evidenced by channels appearing inthe layer of mud which collects in the chamber I about the wall of thedrum, and an uneven flow. of the juice through the chamber I wouldresult. The bafiie ring L however, spreads and joins the streams ofliquid flowing into the chamber I and forms them into a singlecylindrical sheet of the entering fluid, and this sheet as it travelsupwardly in the stratifying chamber I, is acted upon by centrifugalforce and its constituents separate, the heavier moving outwardly fromthe outer side of the sheet and the li hter (is of moving inwardly fromthe inner si the sheet, thus avoiding interference between theoppositely moving constituents as far as possible.

By the time that the upwardly moving fluid has reached the upper end ofthe stratifying chamber I, the impurities have collected about the outerwall of the chamber and the clarified fluid flows through the tubules Ninto the channel M from that depth in the body of liquid in chamber Ifrom which it is desired that itbe drawn. The clarified fluid overflowsthe edge of the flange g, is thrown tangentially into the casing B,flows down the wall of the casing B and into the gutter C, and isdrained out through the outlet pipe 0. When such a quantity of heavyimpurities has collected in the chamber I as a mud that the removal ofthis mud is deemed advisable, the supply of the fluid is discontinued,and water is introduced through the nozzle K until it has displaced thebalance of fluid which has been clarified and which remains in thechamber I, thus effecting a saving of all of the clarified fluid. Thewater is then discontinued and the machine is slowed down, reducing thepressure upon the collected muds. In the case of sugar-containing juicesand solutions, when the pressure is removed by slowing down the machineand will absorb the water remaining in the chamber I after thedisplacement of the balance of the clarified fluid, and will receivetherefrom an increased fluidity which is of advantage when these mudsare to be removed by a plow. When the machine is at speed it would beimpracticable to plowout the mud, but as the speed has been reduced andas the fluidity of the muds has been increased by their absorption ofthe water remaining in the chamber 1, the conditions are right forremoving the mud by moving the plow Q downwardly into the upper end ofthe chamber I by means of the hand wheel 7' and the rack and pinionconnection, bringing the plow into engagement with the mud and againstthe inner wall of the drum, and then operating the hand-wheel r toslowly move of the liquid the muds will expand 4 the plow throughout thelength of the chamber I The plow merely guides the mud under its ownimpetus off of the outer wall of the chamber I and downwardly throughthe openings at the bottom of the machine, where it is directed by ahopper or other device to a discharge opening.

It will be observed that the fluid substance to be clarified isintroduced into the stratifying chamber through subsurface apertures,and this has an important advantage in the clarification of substances,such as sugar juices, which contain lighter impurities consisting offibrous matter, because the eflect of the subsurface introduction is tosubject these light fibrous particles, while in suspension in thecentrifugal, to a considerable pressure which ruptures the air cellswithin their structure, releasing the air and destroying their buoyancy.They then become heavier than the solution in which they are suspendedand collect with the muds, whereas heretofore they have ordinarilyappeared in'a floating scum on top of the clear liquid, where theseparation was brought about in settling tanks, and the like. I havefound in practice that when such subsurface apertures are used there ispractically no scum on the inner surface of the liquid in thestratifying chamber, all of the separated impurities depositingthemselves in layers upon the wall of the chamber, and I experience nodifiiculty with the introduction of the juice, although the layer ofsolid matter on the wall is soon of such depth as to project beyond thesub-surface apertures. In such case the inflow is not hindered, apassage for the incoming fluid remaining beneath the overhanging layerof muds, so that throughout the greater portion of the operation theliquid is actually introduced at a depth greater than the inner surfaceof the mud layer, and consequently the heavier particles are laiddirectly upon the layer of mud, the'lighter particles moving freelytoward the center of the machine without sub- .stantial obstruction fromthe positively moving heavier particles.

What I claim is:

1. A centrifugal separator having an inflow-pipe, an ante-chamber intowhich the inflow-pipe discharges at an acute angle to the surface of theliquid therein contained and in which the substance to be separated isbrought to the angular velocity of the machine, and a stratifyingchamber into which the said substance flows from the ante-chamber;substantially as and for the purpose described.

2. A centrifugal separator having a rotor providing an unobstructedcylindrical stratifying chamber of comparatlvely shallow radial depth,an annular ante-chamber of substantially the same diameter as said haspreviously attained substantially the angular velocity of thecentrifugal apparatus, and beneath the surface of the substanceundergoing stratification therein; substantially as and for the purposedescribed.

4. In a centrifugal'separator, a rotatable I member constructed toprovide an unobstructed stratifying chamber and an antechamber axiallyadjacent to said stratifying chamber and communicating therewith throughaxially directed apertures in a (lividing partition, said ante-chamberhaving its outer wall inclined outwardly to said apertures,substantially as and for the purpose described.

5. In a centrifugal separator, a rotatable member constructed to providea cylindrical stratifying chamber and an ante-chamber axially adjacenttosaid stratifying chamber, and communicating therewith through acircular series of apertures in a dividing partition, said aperturesbeing located below the normal liquid level of said chambers, and abaflie ring mounted in said stratifying chamber opposite said apertures,substantially as and for the purpose described.

6. In a centrifugal separator, a rotatable member constructed to providea cylindrical stratifying chamber free from interior projections and anante-chamber axially adjacent to said stratifying chamber andcommunicating therewith through a circular series of apertures in adividing partition said apertures being located below the normal liquidlevel in said chambers, said ante-chamber being open upon that sidewhich faces the axis of rotation, and a nonfluid to be separated ontothe surface of stantially as and for the purpose described.

7. A centrifugal separator having a stratifying chamber with an annularperipheral flange at its discharge end extending inwardly beyond thenormal liquid level of the substance undergoing stratification andhaving an axially extending perforated ring portion, and removabletubules in the perforations of the ring, whereby the depth from whichthe separated liquid is taken off may be changed by substituting-tubulesof different length of projection into the stratified substance in thechamber; substantially as and for the purpose described.

8. A centrifugal separator having a rotor providing a cylindricalstratifying chamber, an annular ante-chamber in which the liquid isbrought to the velocity of the stratum into which it is to beintroduced, and means for introducing the liquid from the ante-chamberinto the stratifying chamber as an axially moving cylinder, saidstratifying chamber having at its discharge end an inwardly extendingdam establishing a single cylindrical discharge of the clarified liquid.

9. A centrifugal separator having a rotor providing a cylindricalstratifying chamher, an annular ante-chamber in which the liquid isbrought to the velocity of the stratum into which it is to beintroduced,

' and means for introducing the liquid from the ante-chamber into thestratifying chamber as an axially moving cylinder, said stratifyingchamber having at its discharge and an inwardly extending damestablishing a single cylindrical discharge of the clarified liquid froma region of less diameter than thediameter of introduction.

In testimony whereof I afiix my signature, in presence of twowitnesses.

ERNST WILHELM KOPKE.

Witnesses:

Tnos. P. W. GRAY, ALBERT WATERHOUSE.

liquid contained in said ante-chamber; sub-

